| Owing to its excellent electrical property, YBCO thin film is much better than metal in the application for microwave devices. It makes the devices smaller, lighter, and with higher quality factor and lower insertion loss, so, YBCO thin film has been researched intensively. Aiming at the uniformity and property of 3-inch double-sided YBCO thin film, this dissertation had touched the following aspects:Different deposition methods had been compared on the equality of both sides of double-sided thin films. A single inverted cylindrical sputtering (ICS) combined with substrate rotation was used to deposit double-sided YBCO films simultaneously for ensuring the equality of both sides. In comparative research on the substrate rotation modes, such as different in-plane rotations, and out-of-plane rotation, a novel one-axis-driving biaxial rotation had been invented by way of ingenious clamp changing. This rotation mode is simple and reproducible. As it combines out-of-plane rotation with in-plane rotation together, biaxial rotation gives a good opportunity to simultaneously deposit large-area double-sides YBCO thin films. For boosting the deposition rate, two ICS guns were used to deposit films. The deposition rate was increased to 1.0nm/min from 0.3nm/min for each side of 3-inch double-sided YBCO thin films.In the simulation of film thickness distribution, films deposited with ICS had been investigated systematically. The thickness distribution of large-area films could be studied in both directed and diffusive transfer modes by way of target-end projection and twice source-transformations, respectively. The results show that the target length has little effect on the thickness homogeneity. Deposited with biaxial rotation, the films had good thickness distribution. Rotation rate modulation in biaxial rotation could improve the film thickness distribution further, with deviation falling down to only 5%. Beside of the thickness, biaxial rotation had been proved to be suitable for ICS deposition of multi-composition oxide large-area double-sided thin films with homogeneous composition distribution, less than 5% deviation within 3-inch. In addition, biaxial rotation could be useful for other-shape deposition sourcesfor increasing the film uniformity, especially for conic sputter gun.On the film growth mechanism, the film morphologies at initial stage, their evolutions in deposition process, and the morphology variation with deposition temperature and deposition rate had been probed. The results show that, in the range from 760 C to 820 C, the deposition temperature has obvious effect on the morphology but little on crystalline orientation. Due to the substrate inducement,in a relatively wide deposition temperature range, all the crystalline grew with c-axis perpendicular to the substrate surface. A much higher deposition temperature made the clusters form large-size islands, such as needle-like crystalline on LaAlO3.Through systematically research on the deposition parameters, optimized parameter range had been obtained, viz. total pressure ranging from 30 Pa to 35 Pa, ratio of Oxygen to Argon being about 1:2, deposition temperature being 810 C, target-to-substrate distance being 60 mm. The self-template process, namely deposition at 20-50 C higher than the normal deposition temperature for 1 or 2 hours followed deposition at 10-30 C lower than the normal deposition temperature, could improve film crystal structure (FWHMoos down to 0.28 from 0.4 ) and microwave property (RS10GHz,77K down to 0.35m from 0.89m ).By optimizing the deposition parameters, 2-inch double-sided YBCO thin films had been deposited with biaxial rotation, its TC being 89K, its RSHSGHZ, ?SK ranging from 20 to 50m . With rate modulated biaxial rotation, homogeneous 3-inch double-sided YBCO thin films had been deposited. Its TC is ranged from 89.8 to 90.2 K, its Jc is ranged from 2.5 to 2.9 MA/cm2, and its RS is ranged from 50 to 75m at 145GHz, 75K. At 8.5GHz, 77K, the average RS value is about 0.6m . The films had been used by different user...
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